medieval Spanish county and later kingdom, from Vulgar Latin castilla, from Latin castella, plural of castellum "castle, fort, citadel, stronghold" (see castle (n.)); so called in reference to the many fortified places there during the Moorish wars. The name in Spanish is said to date back to c.800. Related: Castilian. As a fine kind of soap, in English from 1610s.

late Old English castel "village" (this sense from a biblical usage in Vulgar Latin); later "large fortified building, stronghold," in this sense from Old North French castel (Old French chastel, 12c.; Modern French château), from Latin castellum "a castle, fort, citadel, stronghold; fortified village," diminutive of castrum "fort," from Proto-Italic *kastro- "part, share;" cognate with Old Irish cather, Welsh caer "town" (and perhaps related to castrare via notion of "cut off;" see caste). In early bibles, castle was used to translate Greek kome "village."

This word also had come to Old English as ceaster and formed the -caster and -chester in place names. Spanish alcazar "castle" is from Arabic al-qasr, from Latin castrum. Castles in Spain translates 14c. French chastel en Espaigne (the imaginary castles sometimes stood in Brie, Asia, or Albania) and probably reflects the hopes of landless knights to establish themselves abroad. The statement that an (English) man's home is his castle is from 16c.

late 14c., "beaver," from Old French castor (13c.), from Latin castor "beaver," from Greek kastor "beaver," literally "he who excels," also the name of one of the divine twins (with Pollux), worshipped by women in ancient Greece as a healer and preserver from disease.

His name was given to secretions of the animal (Latin castoreum), which were used medicinally in ancient times. (Through this association his name replaced the native Latin word for "beaver," which was fiber.) In English, castor is attested in this sense from c. 1600. Modern castor oil is first recorded 1746; it is made from seeds of the plant Ricinus communis but supposedly possesses the laxative qualities (and taste) of beaver juice.

late 14c., "subject to or produced by chance," from Middle French casuel (15c.), from Late Latin casualis "by chance," from Latin casus "chance, occasion, opportunity; accident, event" (see case (n.1)).

Of persons, in the sense of "not to be depended on, unmethodical," it is attested from 1883; meaning "showing lack of interest" is from 1916. Of clothes, "informal," from 1939. Related: Casually.

early 15c., "chance, accident; incidental charge," from casual (adj.) on model of royalty, penalty, etc. Casuality had some currency 16c.-17c. but is now obsolete. Meaning "losses in numbers from a military or other troop" is from late 15c. Meaning "an individual killed, wounded, or lost in battle" is from 1844.

c. 1600, "one who studies and resolves cases of conscience," from French casuiste (17c.) or Spanish casuista (the French word also might be from Spanish), Italian casista, all from Latin casus (see case (n.1)) in its Medieval Latin sense "case of conscience." Often since 17c. in a sinister or contemptuous sense. Related: Casuistic; casuistical; casuistically; casuistry.

Casuistry ... destroys, by distinctions and exceptions, all morality, and effaces the essential difference between right and wrong. [Bolingbroke, 1736]

Old English catt (c. 700), from West Germanic (c. 400-450), from Proto-Germanic *kattuz (source also of Old Frisian katte, Old Norse köttr, Dutch kat, Old High German kazza, German Katze), from Late Latin cattus.

The near-universal European word now, it appeared in Europe as Latin catta (Martial, c. 75 C.E.), Byzantine Greek katta (c. 350) and was in general use on the continent by c. 700, replacing Latin feles. Probably ultimately Afro-Asiatic (compare Nubian kadis, Berber kadiska, both meaning "cat"). Arabic qitt "tomcat" may be from the same source. Cats were domestic in Egypt from c. 2000 B.C.E., but not a familiar household animal to classical Greeks and Romans. The nine lives have been proverbial since at least 1560s.

The Late Latin word also is the source of Old Irish and Gaelic cat, Welsh kath, Breton kaz, Italian gatto, Spanish gato, French chat (12c.). Independent, but ultimately from the same source are words in the Slavic group: Old Church Slavonic kotuka, kotel'a, Bulgarian kotka, Russian koška, Polish kot, along with Lithuanian kate and non-Indo-European Finnish katti, which is from Lithuanian.

Extended to lions, tigers, etc. c. 1600. As a term of contempt for a woman, from early 13c. Slang sense of "prostitute" is from at least c. 1400. Slang sense of "fellow, guy," is from 1920, originally in African-American vernacular; narrower sense of "jazz enthusiast" is recorded from 1931.

Cat's paw (1769, but cat's foot in the same sense, 1590s) refers to old folk tale in which the monkey tricks the cat into pawing chestnuts from a fire; the monkey gets the nuts, the cat gets a burnt paw. Cat bath "hurried or partial cleaning" is from 1953. Cat burglar is from 1907, so called for stealth. Cat-witted "small-minded, obstinate, and spiteful" (1670s) deserved to survive. For Cat's meow, cat's pajamas, see bee's knees.

word-forming element from Latinized form of Greek kata-, before vowels kat-, from kata "down, downward, down from, down to," from PIE *kmt- "down, with, along" (source also of Hittite kattan (adv.) "below, underneath," katta "along with"). Occasionally in Greek it had senses of "against" (catapult) or "wrongly" (catachresis), also "along, through, over, across, concerning." Also sometimes used as an intensive or with a sense of completion of action (catalogue). Very active in ancient Greek, this prefix is found in English mostly in words borrowed through Latin after c. 1500.

usually catacombs, from Old English catacumbas, from Late Latin (400 C.E.) catacumbae (plural), originally the region of underground tombs between the 2nd and 3rd milestones of the Appian Way (where the bodies of apostles Paul and Peter, among others, were said to have been laid), origin obscure, perhaps once a proper name, or dissimilation from Latin cata tumbas "at the graves," from cata- "among" + tumbas. accusative plural of tumba "tomb" (see tomb).

If so, the word perhaps was altered by influence of Latin -cumbere "to lie." From the same source are French catacombe, Italian catacomba, Spanish catacumba. Extended by 1836 in English to any subterranean receptacle of the dead (as in Paris). Related: Catacumbal.

1640s, from French catafalque (17c.), from Italian catafalco "scaffold," from Vulgar Latin *catafalicum, from Greek kata- "down" (see cata-), used in Medieval Latin with a sense of "beside, alongside" + fala "scaffolding, wooden siege tower," a word said to be of Etruscan origin. The Medieval Latin word also yielded Old French chaffaut, chafaud (Modern French échafaud) "scaffold."

"pertaining to Catalonia," also as a noun, "person from Catalonia," late 15c., from the indigenous name, which is said to be of Celtic origin and probably means "chiefs of battle." As a noun meaning "a Catalan," Middle English used Catelaner (mid-14c.), Catellain (early 15c., from French). As a language name in English by 1792. Related: Catalonian (1707).

1580s, in a line of verse, "wanting an unaccented syllable in the last foot," from Late Latin catalecticus, from Greek katalektikos "leaving off," from kata- "down" (see cata-) + legein "to leave off, cease from," from PIE *(s)leg- "to be slack, be languid" (see lax). A complete line is said to be acatalectic.

early 15c., "a waterfall, floodgate," from Latin cataracta "waterfall," from Greek katarhaktes "waterfall, broken water; a kind of portcullis," noun use of an adjective compound meaning "swooping, down-rushing," from kata "down" (see cata-). The second element is traced either to arhattein "to strike hard" (in which case the compound is kat-arrhattein), or to rhattein "to dash, break."

Its alternative sense in Latin of "portcullis" probably was passed through French to form the English meaning "eye disease" (early 15c.), on the notion of "obstruction" (to eyesight).